Annunciator-drop.



W. W. HENRY.

ANNUNGIATOR DROP.

APPLICATION nun) 00124, 1912.

1,107,61 0. Pa nted Aug. 18, 191 1 UNITE sTATns PATENT orrron WILLIAM WEIR HENRY, OF WOLLASTON, MASSACHUSETTS, ASSIGNOR T S. H. COUCH 00., INC., OF ATLANTIC, MASSACHUSETTS.

ANNUNCIATOR-DROP.

Specification of Letters Patent.

Patented Aug. 18, 191st.

To all whom it may concern:

Be it known that I, WVILLIAM IVEII: HENRY, a citizen of the United States, and residing at WVollaston, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Annunciator-Drops, of which the following is a specification.

This invention relates to devices of the annunciator drop type wherein an indicator of light weight is to be rapidly alternated, to and fro; and has special reference to the means for preventing the tendency to rebound on the part of the indicator due to the quick impact of the blow.

In the illustrations which accompany and form part of this specification, Figure 1 is a front View of an annunciator drop, embodying my invention. F ig.2 is a central section of Fig. 1, substantially in the direction indicated by the numerals 22 of Fig. 1, the lower of said numerals having a directing line. The indicator is shown in mid-position. Figs. 3 and 1 are end views showing'the shield in opposite positions. Figs. 5 and 6 are modifications.

The indicator or disk 1 is pivotally mounted at 2 in connection with the supporting frame 8, said pivot 2 also supporting the armature 4 which, in connection with the magnets 5 and 6 are also mounted on frame 3 and form a well-known means for alternating indicator 1. This indicator is provided with a slot 7 here shown conccntrio with pivot 2, and through this slot projccts a lug 8, formed on the armature 1 and adapted to alternately engage the ends of slot 7 for the purpose of imparting motion to the indicator. Lug 8 is not designed to limit the throw of indicator 1 and is preferably formed so that armature 4 has gained a slight momentum before the impulse is given to the indicator, this momentum being slightly greater at the call than at the reset. A wiringcircuit 9 is indicated in diagram in Fig. 1.

The foregoing applies to the general construction of annunciator drop mechanism and does not, in itself, comprise new matter under this application.

As indicator 1 is of light construction and as its movements are rapid, it is necessary to provide means for preventing any tendency toward rebound; so I have invented and shown in the drawings a stop 10 so positioned as to receive the impact of the blow delivered by the indicator and so shaped as to cause that impact to be delivered as a glancing blow. By the term glancing blow is meant one that is not abruptly checked at its first point of impact.

Referring to Figs. 3 and l, it will be noticed that the stop 10 is formed with a rccciving surface somewhat inclined to the plane of motion in which indicator 1 acts, so that when the latter comes in contact with the former, it is permitted a slight further advance, but in a changed direction. This further advance serves to introduce sufficient friction between the parts that are in connection with the moving indicator to overcome the rebound tendency, and this forms the main feature of my invention. As the call blow is preferably sharper than that of resetting the tendency to rebound is greater in the former. This difference of impact could be increased until the rebound on the reset could not overcome the force of gravity,and hence but one of my stops is essential, viz.-that for the calling blow; but in practice this difference is slight and I prefer to provide similar stops on each side. These well-skilled in the art will understand that it is essential that the call should be positive and reliable, and this is best obtained by a sharp, quick blow. The positiveness of action in the rc-setting or return of indicator 1 to non-signaling position is less imperative, though equally desirable.

Fig. 5 shows the wedge 10' reversed, but the action is the same as in the other figures.

In Figs. 3, 4L and 5, three different results of the wedging impact are portrayed in exaggerated form in order that the operation of my invention may be more readily seen; but it will be understood that all three actions may, in practice, be united in effect. In Fig. 3 the wedge stop 10 has caused a slight climbing of the indicator 1 vertically on its pivot 2 to bring an increase of friction against the pivot-head. In Fig. 4 there is shown a slight warping of the indicator against the stop, thereby introducing another element of friction which was lacking before the impact. In Fig. 5 it will be noticed that indicator 1 is shown as being slightly tipped on the pivot 2 thereby increasing the friction on the shank of said pivot. The effect of this increase of friction is most effective at the moment when the rebound tendency is Ill!) greatest and, as found in practice, it will entirely overcome such tendency. In Fig. 6 this wedging effort is applied to the periphery of indicator 1 by the stops 10", causing an increase of friction there and on the pivot 2. Of course it is understood that the warping and wedging effect on the indicator is but momentary, as it finds its thrown position of rest at the initial point of impact.

Attention is called to the unit construction of my device whereby a series of drops may be assembled on a common base through the agency of slotted holes 3,by reason of which, any unit may be replaced by simply loosening the screws which may fasten frame 3 on said base and slipping said frame out of its position. So far as I know I am the first to make each unit complete in itself.

I do not limit myself to the precise construction illustrated.

What I claim is 1. An annunciator drop comprising a frame, an eleotromagnet mounted on said frame, and an indicator movably mounted in connection with said frame and adapted to be thrown from a position of rest by said magnet; in combination with a rigid stop adapted to receive the impact of the moving indicator, said stop being so shaped as to permit a slight continued advance of said indicator beyond its initial point of impact, and so positioned as to automatically compel the indicator to return to said initial point of impact as its final thrown position.

to receive the impact of said indicator as a glancing blow, and so positioned as to automatically compel said indicator to ultimately come to rest at its position of initial impact.

3. An indicator adapted to be thrown from a position of rest, means for causing such throw, and a stop adapted to receive the impact of said indicator as a glancing blow, said stop being so positioned as to ultimately bring said indicator to rest at the position of initial impact.

4. An indicator adapted to be thrown from a position of rest, means for causing such throw, and a rigid stop adapted to receive the impact of the moving indicator, said stop being so shaped as to permit a slight advance of said indicator beyond its first point ofimpact, and so positioned as to compel said indicator to automatically return to said first point of impact as its final thrown position.

In testimony whereof I have afiixed my signature, in presence of two witnesses.

WILLIAM WEIR HENRY.

WVitnesses SAMUEL H. CoUoH, WALDo B. FAY.

Copier of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C." 

